Solve 5x ā 3 = ā18
The solution of 5x ā 3 = ā18 is x = -3.
How to work it out
- 1
The goal is to get x alone. Undo the operations in the opposite order: first the subtraction, then the multiplication.
- 2
Add 3 to both sides:
- 3
Divide both sides by 5:
- 4
Check: put x = -3 back into the equation.
LaTeX source of the formulas on this page
\[ 5x - 3 = -18\ \Rightarrow\ x = -3 \]
\[ 5x - 3 = -18 \]
\[ 5x - 3 + 3 = -18 + 3 \ \Rightarrow\ 5x = -15 \]
\[ \frac{5x}{5} = \frac{-15}{5} \ \Rightarrow\ x = -3 \]
\[ 5\cdot(-3) - 3 = -15 - 3 = -18 \checkmark \]Trying values of x in 5x ā 3 = ā18
| x | 5x ā 3 | Equals -18? |
|---|---|---|
| -5 | -28 | no |
| -4 | -23 | no |
| -3 | -18 | yes |
| -2 | -13 | no |
| -1 | -8 | no |
Questions
What is x in 5x ā 3 = ā18?
The solution of 5x ā 3 = ā18 is x = -3.
How do you solve 5x ā 3 = ā18?
Add 3 to both sides to get 5x = -15, then divide both sides by 5 to get x = -3.
How do I check the answer?
Replace x by -3: 5(-3) ā 3 = -18, which is -18.